Benedict nodded to Charles Whymper and began to try and think of something else. He thought back to his experience with Anne Moony and the bowtruckles, they seemed quite placid once they had their twigs into some fresh woodlice, but could they be persuaded to help.

Ben's skin went cold thought when the creature appeared... a dementor! What was that doing here and why? He shivered as the risk of failure set in but he tried to steel his heart. A Gryffindor is brave, a Gryffinor is noble, he had read enough of these stories to know what to try. He pulled out his wand and stepped forward "Expecto Patronum! he said loudly. His wand glowed and rivers of pale blue light flew out like a stream. Contained within this stream was the very faint and whispy outline of some kind of shark, long and slender with an elongated caudal fin. It spun and lashed at the creature but Benedict had not given spell enough for it to corporeal and the clued dissipated as the creature swept forwards and through it, only briefly pausing to work out which student had tried to chase him away and make a beeline straight for Benedict.